1Q22 Challenge - A tiny stereo power amp

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normula1normula1 Frets: 639
edited January 2022 in Making & Modding
This just about meets the brief, primarily 'cos I drilled some holes and soldered a handful of wires

https://thepihut.com/products/adafruit-stereo-20w-class-d-audio-amplifier-max9744
was sent to me in mailshot, so got Mrs Normula1 to buy it for my birthday. Rummaged through my boxes of bits for all the other parts and a wall wart power supply for an external hard drive to power it.

Fired it up briefly this evening and it won't win any awards in the cork sniffing stakes but it def works.

Stereo in and out, in theory 20 watts per side but can't see me getting anywhere near that with my 2amp PSU.

One word of warning is that the onboard power connector is centre positive.




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Comments

  • inewhaminewham Frets: 135
    Thanks for that I was looking for something similar yesterday

    ( PS the long tail on the -ve looks like it might touch the case at some point, you might want to clip that )

    Ian
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  • normula1normula1 Frets: 639
    Already clipped them before I screwed the bottom plate on with a suitable bit of card as an insulator  :)
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  • Does it not need some sort of heat sink (even if it's just the metal box, but I can't see anything attached to it)?  Or do class D amps run so efficiently they don't need it?
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  • normula1normula1 Frets: 639
    Nope, the documentation says not due to the efficiency. 
    I gave it a workout over the weekend and yes it works, not convinced I'm too enamoured of the tone. I built it so I had something to use whilst I rebuild my valve power amp (a couple of the valve sockets have gone after 60 odd years of use and can't retension them)

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  • inewhaminewham Frets: 135
    Are you using a preamp or just going straight into the power amp?

    Ian
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  • normula1normula1 Frets: 639
    I'm using a ridiculously over complex setup of guitar into a few pedals into amps with load boxes (the amps effectively become pre-amps) then into a TC GMajor 2 which splits the output to stereo, with a Neo Ventilator in parallel then a Yersasov Iron cab into a stereo power amp and then a 2*12 wired for stereo with Celestion F12-x200s. 
    But you could just as easily use a pre-amp pedal. I've nearly convinced myself to buy a Boss IR 200.
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  • inewhaminewham Frets: 135
    Wow, i feel rather inadequate :) I'm just taking the 2 line outs from my JC22 through this tiny amp into a couple of old hi-fi  to get a bit more physical separation since you don't really notice the JC is stereo when the speakers are 2" apart. It seems to do the job quite well.

    Ian
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  • normula1normula1 Frets: 639
    I really do all that to have the amps (a '73 JMP Marshall and a Boogie Studio 22+) cooking nicely but at a volume that's house, neighbour and tinnitus friendly.
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